The Linux kernel version 3.3-rc1 and later is affected by a vulnerability lies in the processing of incoming L2CAP commands - ConfigRequest, and ConfigResponse messages. This info leak is a result of uninitialized stack variables that may be returned to an attacker in their uninitialized state. By manipulating the code flows that precede the handling of these configuration messages, an attacker can also gain some control over which data will be held in the uninitialized stack variables. This can allow him to bypass KASLR, and stack canaries protection - as both pointers and stack canaries may be leaked in this manner. Combining this vulnerability (for example) with the previously disclosed RCE vulnerability in L2CAP configuration parsing (CVE-2017-1000251) may allow an attacker to exploit the RCE against kernels which were built with the above mitigations. These are the specifics of this vulnerability: In the function l2cap_parse_conf_rsp and in the function l2cap_parse_conf_req the following variable is declared without initialization: struct l2cap_conf_efs efs; In addition, when parsing input configuration parameters in both of these functions, the switch case for handling EFS elements may skip the memcpy call that will write to the efs variable: ... case L2CAP_CONF_EFS: if (olen == sizeof(efs)) memcpy(&efs, (void *)val, olen); ... The olen in the above if is attacker controlled, and regardless of that if, in both of these functions the efs variable would eventually be added to the outgoing configuration request that is being built: l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS, sizeof(efs), (unsigned long) &efs); So by sending a configuration request, or response, that contains an L2CAP_CONF_EFS element, but with an element length that is not sizeof(efs) - the memcpy to the uninitialized efs variable can be avoided, and the uninitialized variable would be returned to the attacker (16 bytes).

An issue was discovered in the size of the default stack guard page on PAX Linux (originally from GRSecurity but shipped by other Linux vendors), specifically the default stack guard page is not sufficiently large and can be "jumped" over (the stack guard page is bypassed), this affects PAX Linux Kernel versions as of June 19, 2017 (specific version information is not available at this time).

The Linux Kernel imposes a size restriction on the arguments and environmental strings passed through RLIMIT_STACK/RLIM_INFINITY (1/4 of the size), but does not take the argument and environment pointers into account, which allows attackers to bypass this limitation. This affects Linux Kernel versions 4.11.5 and earlier. It appears that this feature was introduced in the Linux Kernel version 2.6.23.

An issue was discovered in the size of the stack guard page on Linux, specifically a 4k stack guard page is not sufficiently large and can be "jumped" over (the stack guard page is bypassed), this affects Linux Kernel versions 4.11.5 and earlier (the stackguard page was introduced in 2010).

net/netfilter/xt_osf.c in the Linux kernel through 4.14.4 does not require the CAP_NET_ADMIN capability for add_callback and remove_callback operations, which allows local users to bypass intended access restrictions because the xt_osf_fingers data structure is shared across all net namespaces.

net/netfilter/nfnetlink_cthelper.c in the Linux kernel through 4.14.4 does not require the CAP_NET_ADMIN capability for new, get, and del operations, which allows local users to bypass intended access restrictions because the nfnl_cthelper_list data structure is shared across all net namespaces.

The waitid implementation in kernel/exit.c in the Linux kernel through 4.13.4 accesses rusage data structures in unintended cases, which allows local users to obtain sensitive information, and bypass the KASLR protection mechanism, via a crafted system call.

The acpi_ns_evaluate() function in drivers/acpi/acpica/nseval.c in the Linux kernel through 4.12.9 does not flush the operand cache and causes a kernel stack dump, which allows local users to obtain sensitive information from kernel memory and bypass the KASLR protection mechanism (in the kernel through 4.9) via a crafted ACPI table.

The acpi_ps_complete_final_op() function in drivers/acpi/acpica/psobject.c in the Linux kernel through 4.12.9 does not flush the node and node_ext caches and causes a kernel stack dump, which allows local users to obtain sensitive information from kernel memory and bypass the KASLR protection mechanism (in the kernel through 4.9) via a crafted ACPI table.

The acpi_ds_create_operands() function in drivers/acpi/acpica/dsutils.c in the Linux kernel through 4.12.9 does not flush the operand cache and causes a kernel stack dump, which allows local users to obtain sensitive information from kernel memory and bypass the KASLR protection mechanism (in the kernel through 4.9) via a crafted ACPI table.

The acpi_ns_terminate() function in drivers/acpi/acpica/nsutils.c in the Linux kernel before 4.12 does not flush the operand cache and causes a kernel stack dump, which allows local users to obtain sensitive information from kernel memory and bypass the KASLR protection mechanism (in the kernel through 4.9) via a crafted ACPI table.

The mm subsystem in the Linux kernel through 4.10.10 does not properly enforce the CONFIG_STRICT_DEVMEM protection mechanism, which allows local users to read or write to kernel memory locations in the first megabyte (and bypass slab-allocation access restrictions) via an application that opens the /dev/mem file, related to arch/x86/mm/init.c and drivers/char/mem.c.

The do_shmat function in ipc/shm.c in the Linux kernel through 4.9.12 does not restrict the address calculated by a certain rounding operation, which allows local users to map page zero, and consequently bypass a protection mechanism that exists for the mmap system call, by making crafted shmget and shmat system calls in a privileged context.

An elevation of privilege vulnerability in the kernel security subsystem could enable a local malicious application to to execute code in the context of a privileged process. This issue is rated as High because it is a general bypass for a kernel level defense in depth or exploit mitigation technology. Product: Android. Versions: Kernel-3.18. Android ID: A-33351919.

An information disclosure vulnerability in the Qualcomm bootloader could help to enable a local malicious application to to execute arbitrary code within the context of the bootloader. This issue is rated as High because it is a general bypass for a bootloader level defense in depth or exploit mitigation technology. Product: Android. Versions: Kernel-3.18. Android ID: A-32370952. References: QC-CR#1082755.

The aio_mount function in fs/aio.c in the Linux kernel before 4.7.7 does not properly restrict execute access, which makes it easier for local users to bypass intended SELinux W^X policy restrictions, and consequently gain privileges, via an io_setup system call.

drivers/vfio/pci/vfio_pci.c in the Linux kernel through 4.8.11 allows local users to bypass integer overflow checks, and cause a denial of service (memory corruption) or have unspecified other impact, by leveraging access to a vfio PCI device file for a VFIO_DEVICE_SET_IRQS ioctl call, aka a "state machine confusion bug."

Race condition in the audit_log_single_execve_arg function in kernel/auditsc.c in the Linux kernel through 4.7 allows local users to bypass intended character-set restrictions or disrupt system-call auditing by changing a certain string, aka a "double fetch" vulnerability.

The is_ashmem_file function in drivers/staging/android/ashmem.c in a certain Qualcomm Innovation Center (QuIC) Android patch for the Linux kernel 3.x mishandles pointer validation within the KGSL Linux Graphics Module, which allows attackers to bypass intended access restrictions by using the /ashmem string as the dentry name.

The arch_pick_mmap_layout function in arch/x86/mm/mmap.c in the Linux kernel through 4.5.2 does not properly randomize the legacy base address, which makes it easier for local users to defeat the intended restrictions on the ADDR_NO_RANDOMIZE flag, and bypass the ASLR protection mechanism for a setuid or setgid program, by disabling stack-consumption resource limits.

The Linux kernel before 4.5 allows local users to bypass file-descriptor limits and cause a denial of service (memory consumption) by leveraging incorrect tracking of descriptor ownership and sending each descriptor over a UNIX socket before closing it. NOTE: this vulnerability exists because of an incorrect fix for CVE-2013-4312.

The LIST_POISON feature in include/linux/poison.h in the Linux kernel before 4.3, as used in Android 6.0.1 before 2016-03-01, does not properly consider the relationship to the mmap_min_addr value, which makes it easier for attackers to bypass a poison-pointer protection mechanism by triggering the use of an uninitialized list entry, aka Android internal bug 26186802, a different vulnerability than CVE-2015-3636.

arch/arm64/kernel/sys.c in the Linux kernel before 4.0 allows local users to bypass the "strict page permissions" protection mechanism and modify the system-call table, and consequently gain privileges, by leveraging write access.

The ovl_setattr function in fs/overlayfs/inode.c in the Linux kernel through 4.3.3 attempts to merge distinct setattr operations, which allows local users to bypass intended access restrictions and modify the attributes of arbitrary overlay files via a crafted application.

The sco_sock_bind function in net/bluetooth/sco.c in the Linux kernel before 4.3.4 does not verify an address length, which allows local users to obtain sensitive information from kernel memory and bypass the KASLR protection mechanism via a crafted application.

The (1) pptp_bind and (2) pptp_connect functions in drivers/net/ppp/pptp.c in the Linux kernel through 4.3.3 do not verify an address length, which allows local users to obtain sensitive information from kernel memory and bypass the KASLR protection mechanism via a crafted application.

The prepend_path function in fs/dcache.c in the Linux kernel before 4.2.4 does not properly handle rename actions inside a bind mount, which allows local users to bypass an intended container protection mechanism by renaming a directory, related to a "double-chroot attack."

arch/x86/kernel/entry_64.S in the Linux kernel before 3.19.2 does not prevent the TS_COMPAT flag from reaching a user-mode task, which might allow local users to bypass the seccomp or audit protection mechanism via a crafted application that uses the (1) fork or (2) close system call, as demonstrated by an attack against seccomp before 3.16.

The stack randomization feature in the Linux kernel before 3.19.1 on 64-bit platforms uses incorrect data types for the results of bitwise left-shift operations, which makes it easier for attackers to bypass the ASLR protection mechanism by predicting the address of the top of the stack, related to the randomize_stack_top function in fs/binfmt_elf.c and the stack_maxrandom_size function in arch/x86/mm/mmap.c.

Race condition in the handle_to_path function in fs/fhandle.c in the Linux kernel through 3.19.1 allows local users to bypass intended size restrictions and trigger read operations on additional memory locations by changing the handle_bytes value of a file handle during the execution of this function.

The V8ThrowException::createDOMException function in bindings/core/v8/V8ThrowException.cpp in the V8 bindings in Blink, as used in Google Chrome before 40.0.2214.111 on Windows, OS X, and Linux and before 40.0.2214.109 on Android, does not properly consider frame access restrictions during the throwing of an exception, which allows remote attackers to bypass the Same Origin Policy via a crafted web site.

fs/namespace.c in the Linux kernel before 4.0.2 processes MNT_DETACH umount2 system calls without verifying that the MNT_LOCKED flag is unset, which allows local users to bypass intended access restrictions and navigate to filesystem locations beneath a mount by calling umount2 within a user namespace.

The Btrfs implementation in the Linux kernel before 3.19 does not ensure that the visible xattr state is consistent with a requested replacement, which allows local users to bypass intended ACL settings and gain privileges via standard filesystem operations (1) during an xattr-replacement time window, related to a race condition, or (2) after an xattr-replacement attempt that fails because the data does not fit.

The vdso_addr function in arch/x86/vdso/vma.c in the Linux kernel through 3.18.2 does not properly choose memory locations for the vDSO area, which makes it easier for local users to bypass the ASLR protection mechanism by guessing a location at the end of a PMD.

The __switch_to function in arch/x86/kernel/process_64.c in the Linux kernel through 3.18.1 does not ensure that Thread Local Storage (TLS) descriptors are loaded before proceeding with other steps, which makes it easier for local users to bypass the ASLR protection mechanism via a crafted application that reads a TLS base address.

The Linux kernel through 3.17.4 does not properly restrict dropping of supplemental group memberships in certain namespace scenarios, which allows local users to bypass intended file permissions by leveraging a POSIX ACL containing an entry for the group category that is more restrictive than the entry for the other category, aka a "negative groups" issue, related to kernel/groups.c, kernel/uid16.c, and kernel/user_namespace.c.

The paravirt_ops_setup function in arch/x86/kernel/kvm.c in the Linux kernel through 3.18 uses an improper paravirt_enabled setting for KVM guest kernels, which makes it easier for guest OS users to bypass the ASLR protection mechanism via a crafted application that reads a 16-bit value.

arch/x86/kernel/tls.c in the Thread Local Storage (TLS) implementation in the Linux kernel through 3.18.1 allows local users to bypass the espfix protection mechanism, and consequently makes it easier for local users to bypass the ASLR protection mechanism, via a crafted application that makes a set_thread_area system call and later reads a 16-bit value.

kernel/trace/trace_syscalls.c in the Linux kernel through 3.17.2 does not properly handle private syscall numbers during use of the perf subsystem, which allows local users to cause a denial of service (out-of-bounds read and OOPS) or bypass the ASLR protection mechanism via a crafted application.

The do_remount function in fs/namespace.c in the Linux kernel through 3.16.1 does not maintain the MNT_LOCK_READONLY bit across a remount of a bind mount, which allows local users to bypass an intended read-only restriction and defeat certain sandbox protection mechanisms via a "mount -o remount" command within a user namespace.

The snd_ctl_elem_add function in sound/core/control.c in the ALSA control implementation in the Linux kernel before 3.15.2 does not properly maintain the user_ctl_count value, which allows local users to cause a denial of service (integer overflow and limit bypass) by leveraging /dev/snd/controlCX access for a large number of SNDRV_CTL_IOCTL_ELEM_REPLACE ioctl calls.

arch/mips/include/asm/thread_info.h in the Linux kernel before 3.14.8 on the MIPS platform does not configure _TIF_SECCOMP checks on the fast system-call path, which allows local users to bypass intended PR_SET_SECCOMP restrictions by executing a crafted application without invoking a trace or audit subsystem.

The capabilities implementation in the Linux kernel before 3.14.8 does not properly consider that namespaces are inapplicable to inodes, which allows local users to bypass intended chmod restrictions by first creating a user namespace, as demonstrated by setting the setgid bit on a file with group ownership of root.

The Netlink implementation in the Linux kernel through 3.14.1 does not provide a mechanism for authorizing socket operations based on the opener of a socket, which allows local users to bypass intended access restrictions and modify network configurations by using a Netlink socket for the (1) stdout or (2) stderr of a setuid program.

Use-after-free vulnerability in net/unix/af_unix.c in the Linux kernel before 4.3.3 allows local users to bypass intended AF_UNIX socket permissions or cause a denial of service (panic) via crafted epoll_ctl calls.

The aac_compat_ioctl function in drivers/scsi/aacraid/linit.c in the Linux kernel before 3.11.8 does not require the CAP_SYS_RAWIO capability, which allows local users to bypass intended access restrictions via a crafted ioctl call.

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